1. Field of the Invention
This invention relates generally to modular space structures, and more particularly to a modular space structure erected in outer space from expandable modules transported in the payload bay of a space shuttle or by expendable rocket which expand to increase the volume of enclosed area and are joined to like modules to form a central enclosed area between the modules.
2. Brief Description of the Prior Art
Toroidal space station structures have been designed that could be lifted into earth orbit in one shot, and then deployed out to their operational form. The more recent Skylab is an example of a one-shot space station that was put into earth orbit. Severe size and weight restrictions of such one-shot space stations limit the effective working life of the space station and limit the exhaustible staples required to support life for its inhabitants. The size and weight restrictions also limit other necessities such as providing artificial gravity to overcome the effect of weightlessness over extended periods of time.
Very large self-sufficient space station structures have also been proposed which would support many forms of terrestrial life. Most self-supporting space structures would be so large as to make it impractical to erect them piecemeal on earth and lift them piece by piece to be assembled in earth orbit. It has been suggested that they may have to be fabricated in earth orbit from raw materials carried on a space shuttle or from earth's moon.
The large wheel-like structures are a result of the concept that artificial gravity would be necessary for long-term habitation. The current state of the art has replaced the wheel designs with living and working modules connected together around a hub with outwardly extending feelers, collectors and manipulators which resemble a robotic spider.
State of the art "clustered module" concepts have been proposed by the National Aeronautics and Space Administration (NASA) and from NASA contractors such as McDonnell Douglas Astronautics Co., TRW Space and Technology Group, Rockwell International, and Boeing Aerospace Company.
The above mentioned "clustered modules" are aggregations or conglomerations which feature a central open frame structure having various cylindrical modules spaced thereabout and connected together by a network of pressurized tubes. The modules are interconnected by joining them together end to end or joining their ends together with pressurized tubes. Later shuttle trips would add modules or appendages to that basic structure. The modules are suggested to be approximately 14 ft. in diameter by 24 ft. long. The volume of each such cylinder would be 3,700 cu. ft. One of these cylinders would house a crew of six to eight astronauts. One disadvantage of the current clustered module designs is that the total area is linear and there is no central enclosure, resulting in segmented crowded habitable areas. There is no central enclosure common to the modules and the total useful volume is spread out over spaced apart modules connected by tubes.
Another disadvantage of the current clustered module designs is that each module requires an expensive separate launch to create a large structure, whereas with the present invention the amount of usable area or volume can be doubled or tripled with a single launch, and after two launches it is possible to create a large structure having a central enclosed area common to the modules which may be used for various purposes. The equivalent number of modules of the prior art and currently proposed space stations would provide only spaced apart modules with no common central enclosure.
There are several patents which disclose space modules capable of forming various space station configurations, most of which consist of a ring-like shape having a central hub. Others provide various modules to serve as the core of the station structure.
Hogan, U.S. Pat. No. 4,057,207 discloses a module having the geometry of joined truncated icosohedra, which when a plurality of them are joined together, form a space vehicle. The vehicle formed would consist of two types of rings or four varieties of helices. The helical configuration would allow simple gravity to be generated by way of rotation and also serve as a habitable framework about which a large cylindrical space structure could be built. Hogan teaches joining the modules more or less end-to-end in a linear manner. The actual usable space in such configurations is limited to a relatively long and narrow tube.
Schneider et al, U.S. Pat. No. 4,579,302 discloses a shuttle-launch triangular space station deployable in earth orbit. The framework is comprised of three trusses having generally planar faces comprised of foldable struts which expand and lock into structural engagement forming a repetition of equilateral triangles and non-folding struts interconnecting the two faces. Cylindrical modules may be secured to the three apexes of the framework and connected together by tunnels. The modules may be used for habitat, logistics, service, and laboratory.
Berglund, U.S. Pat. No. 3,169,725 discloses a compact folded space station which is collapsed and transported in the payload bay of a launch vehicle. The station utilizes rigid cylindrical sections, equipped for life support and experiments before launch, joined together by flexible connectors. These sections are connected to a central hub and are erectable to form a rigid hexagonal tubular ring thereabout in earth orbit. The sections are connected to the hub by spoke-like telescoping struts and may also be interconnected by inflatable access tubes.
Nesheim, U.S. Pat. No. 3,332,640 discloses a preassembled space station comprising tubular sections pivotally connected end to end to form a ring-like structure.
Berce, et al, U.S. Pat. No. 3,792,558 is not a space station, but rather a transportable, ground supported dwelling structure which requires a rigid parallelopedic mounting frame structure having longitudinal, transverse, and vertical beam-like structural members. The frame structure serves as the shipping container, or "transcontainer" for rectangular "hull" members and as the base framework onto which the room-like "hulls" are mounted to form a dwelling. The modular hulls require a rectangular flange around all the edges to enable their fixing onto the framework.
Taylor, U.S. Pat. No. 4,562,979 discloses an expandable spacecraft which includes at least one main cylindrical body of generally waffle-type structure which has a plurality of flanges extending radially from the body. An auxiliary housing is connected to the main body and slidably and telescopically received therein. The auxiliary housing can be expanded outwardly from the main body to increase the volume of the assembly to a degree. There is no suggestion of joining the modules to like modules to form a common central enclosed area.
Ganssle et al, U.S. Pat. No. 4,395,004 discloses spacecraft structures suitable for mounting in the payload bay of a space shuttle. Each structure comprises a plurality of modules in the form of a truss network secured to one another. Various equipment can be attached to the trusses.
Truss, U.S. Pat. No. 4,480,415 discloses an extendible open boom structure for use in constructing orbital platforms.
Bull, U.S. Pat. No. 4,792,108 discloses a pair of compartments tethered together which are mounted in spaced relation by an extendible pole.
The present invention is distinguished over the prior art in general, and these patents in particular by a modular space structure having a central enclosed area which is erected in outer space from modules transported by a reusable space shuttle or an expendable rocket. Each module comprises an outer member and one or more inner members carried telescopically therein forming a complete enclosure to serve as a small self contained space structure capable of being equipped for life support. Each inner member has slightly less volume than the outer member in which it is nested. As each inner member is extended, the interior volume is increased and a larger enclosure is formed. A two member module, when extended, would nearly double the amount of initial enclosed usable space, and an extended three member module would nearly triple the amount of initial enclosed usable space. The expandable modules serve as building blocks which may be joined to other like modules in various configurations to form a complete enclosure about a common interior volume with the modules forming the walls of the enclosure to create increasingly larger space structure units having a plurality of enclosed central areas. Passageways allow occupant communication between the modules and the central enclosure. Adapter modules and various other devices such as docking ports for docking space craft to the structure and thrust generating or communication devices may be secured to the modules.